[ADT] Get rid of use of LLVM_NOEXCEPT in CachedHashString.h.

LLVM_NOEXCEPT is no longer necessary (yay).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284876 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed